In-silico investigation of antibacterial herbal compounds in order to find new antibiotic against Staphylococcus aureus and its resistant subtypes

Staphylococcus aureus can cause different diseases. S. aureus resistant strains such as methicillin-resistant strains recently have become a big problem in hospital infections. These strains respond to some current antibiotics, but these effects may not last long due to the constant mutations of these bacteria. Therefore, research on other factors, such as herbal compounds, may play a crucial role in inhibition. Hence, in this research, we have tried to find herbal efficient compounds to inhibit S. aureus and Methicillin-Resistant Staphylococcus aureus (MRSA) important proteins and infections. 2000 compounds from 87 medicinal plants were collected from related articles. S. aureus and MRSA important protein structures were obtained from the RCSB PDB database. In addition, the PubChem database was used to achieve the structure of the compounds. Molecular docking analysis of compounds was performed against CrtM(diapophytoene synthase), DNA gyrase, SarA(Staphylococcal Accessory Regulator A), and PBP2a(penicillin-binding protein 2A) proteins which were the most noticeable proteins causing S. aureus and MRSA infections, and finally, the features of top compounds were gained from different databases. The results showed that Berbamine, Galangin, Hypericin, Protohypericin, Pseudohypericin, and Berberine were the best compounds with high binding affinity to each four mentioned proteins with no or minimum side effect. Berbamine had the highest binding affinity to all four proteins. According to the results Mahonia aquifolium, Beberis Vulgaris, Chelidonium majus, Rheum Ribes, Hypericum perforatum, and Hibiscus sabdariffa had the best active compounds against S. aureus important proteins. These medicinal compounds may be effective as antibiotics against S. aureus resistant subtypes because they have no or minimum side effects and are beneficial for health. If it is proven experimentally that the aforementioned herbal compounds are effective on S. aureus, these compounds could help treat diseases caused by S. aureus.